• Title/Summary/Keyword: Comet-assay

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Lymphocyte DNA damage and plasma antioxidant status in Korean subclinical hypertensive patients by glutathione S-transferase polymorphism

  • Han, Jeong-Hwa;Lee, Hye-Jin;Choi, Hee Jeong;Yun, Kyung Eun;Kang, Myung-Hee
    • Nutrition Research and Practice
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    • v.11 no.3
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    • pp.214-222
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    • 2017
  • BACKGROUND/OBJECTIVES: Glutathione S-transferase (GST) forms a multigene family of phase II detoxification enzymes which are involved in the detoxification of xenobiotics by conjugating substances with glutathione. The aim of this study is to assess the antioxidative status and the degree of DNA damage in the subclinical hypertensive patients in Korea using glutathione S-transferase polymorphisms. SUBJECTS/METHODS: We examined whether DNA damage and antioxidative status show a difference between GSTM1 or GSTT1 genotype in 227 newly diagnosed, untreated (systolic blood pressure $(BP){\geq}130mmHg$ or diastolic $BP{\geq}85mmHg$) subclinical hypertensive patients and 130 normotensive subjects (systolic BP < 120 mmHg and diastolic BP < 80 mmHg). From the blood of the subjects, the degree of the DNA damage in lymphocyte, the activities of erythrocyte superoxide dismutase, the catalase, and the glutathione peroxidase, the level of glutathione, plasma total radical-trapping antioxidant potential (TRAP), anti-oxidative vitamins, as well as plasma lipid profiles and conjugated diene (CD) were analyzed. RESULTS: Of the 227 subjects studied, 68.3% were GSTM1 null genotype and 66.5% were GSTT1 null genotype. GSTM1 null genotype had an increased risk of hypertension (OR: 2.104, CI: 1.38-3.35), but no significant association in GSTT1 null genotype (OR 0.982, CI: 0.62-1.55). No difference in erythrocyte activities of superoxide dismutase, catalase, or glutathione peroxidase, and plasma TRAP, CD, lipid profiles, and GSH levels were observed between GSTM1 or GSTT1 genotype. Plasma levels of ${\alpha}-tocopherol$ increased significantly in GSTT1 wild genotype (P < 0.05); however, plasma level of ${\beta}-carotene$ increased significantly in GSTT1 null genotype (P < 0.01). DNA damage assessed by the Comet assay was significantly higher in GSTM1 null genotype than wild genotype (P < 0.05). CONCLUSIONS: These results confirm the association between GSTM1 null genotype and risk of hypertension as they suggest that GSTM1 null genotype leads to an increased oxidative stress compared with wild genotype.

The Effect of Alpha-tocopherol Supplementation on the Improvement of Antioxidant Status and Lymphocyte DNA Damage in Postmenopausal Women (비타민 E 보충섭취가 폐경기 여성의 혈장 항산화 영양상태 및 DNA 손상 개선에 미치는 영향)

  • Kim, Chang-Suk;Kang, Hae-Jin;Lee, Soon-Hee;Park, Yoo-Kyoung;Kang, Myung-Hee
    • Journal of Nutrition and Health
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    • v.40 no.8
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    • pp.708-718
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    • 2007
  • The purpose of this project was to evaluate whether vitamin E supplementation could improve the antioxidant status and lymphocyte DNA damage in Korean postmenopausal women. This was double blinded, placebo-controlled trial. Thirty-five subject were randomized to receive either placebo 400 mg/capsule or natural $\alpha$-tocopherol 400 IU/capsule, 2 times a day for 6 weeks. We measured plasma vitamin C, $\alpha$-tocopherol, $\gamma$-tocopherol, $\alpha$-carotenoid, $\beta$-carotenoid, lycopene concentration and tail length, %DNA in tail, tail moment in lymphocyte DNA damage index. Vitamin E supplementation group had significantly increased plasma vitamin C(p<0.05), $\alpha$-tocopherol(p<0.000), whereas $\gamma$-tocopherol(p<0.000) and tail length(p<0.05) were significantly decreased. However, placebo supplementation group also had significantly increased plasma vitamin C(p<0.05). In conclusion, our study shows that vitamin E supplementation to Korean postmenopausal women may partially improve antioxidant status and lymphocyte DNA damage.

Oxidative Stress of Mouse Fed Irradiated Diet Containing High Unsaturated Fatty Acid (방사선 조사된 고불포화지방산 식이를 섭취한 Mouse의 산화적 스트레스)

  • Seo, Dae-Young;Park, Sun-Young;Kang, Myoung-Hee;Suh, Kwang-Sun;Ly, Sun-Yung
    • Journal of Nutrition and Health
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    • v.39 no.7
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    • pp.599-609
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    • 2006
  • In this study, we investigated the in vivo effect by intake of the irradiated foods such as mackerel and sesame seed which are high in unsaturated fatty acid through TBARS (thiobarbituric acid reactive subtance) and the tissue pathological and genotoxicological test. Thirty two ICR mice are divided into four groups, one non-irradiated (control) group and three irradiated (5, 10, 20 kGy, respectively) groups. Sesame seed and pulverized mackerel in modified AIN93M diet were mixed together then divided into four identical parts. Three parts of them were irradiated by doses of 5, 10, and 20 kGy. These experimental diet were fed to each group for 4, 8 and] 6 weeks. The results of the study were as follows: No significant differences in weight gain were found in each group. Peroxide value of the irradiated diet was higher than that of the non-radiated one and also increased according to the storage period. TBA values in plasma, liver, kidney and Peyer's patch were not significantly different among 4 groups. DNA% in tail, tail length (TL) and tail moment (TM) values of the blood lymphocyte in 4, 8 and 16 week groups and the liver in 16 week group were much measured over the control DNA % in tail of kidney of 8 week group was significantly than the control and TL and TM of 8 week and TM of 16 week groups showed a tendency of higher values. By Peyer's DNA % in tail of 8 week group, DNA % in tail and TM of 16 week groups increased significantly over the control, Ultrastructural examination shows myeline figures and swollen mitochondria in parietal cells and intestinal epithelial cells of 8 and 16 weeks groups. After this study, we need further investigations on the safety of highly consumed foods which contain high contents of unsaturated fatty acid, largely imported and which are possible to be irradiated.

Early Activation of Apoptosis and Caspase-independent Cell Death Plays an Important Role in Mediating the Cytotoxic and Genotoxic Effects of WP 631 in Ovarian Cancer Cells

  • Gajek, Arkadiusz;Denel-Bobrowska, Marta;Rogalska, Aneta;Bukowska, Barbara;Maszewski, Janusz;Marczak, Agnieszka
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.18
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    • pp.8503-8512
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    • 2016
  • The purpose of this study was to provide a detailed explanation of the mechanism of bisanthracycline, WP 631 in comparison to doxorubicin (DOX), a first generation anthracycline, currently the most widely used pharmaceutical in clinical oncology. Experiments were performed in SKOV-3 ovarian cancer cells which are otherwise resistant to standard drugs such as cis-platinum and adriamycin. As attention was focused on the ability of WP 631 to induce apoptosis, this was examined using a double staining method with Annexin V and propidium iodide probes, with measurement of the level of intracellular calcium ions and cytosolic cytochrome c. The western blotting technique was performed to confirm PARP cleavage. We also investigated the involvement of caspase activation and DNA degradation (comet assay and immunocytochemical detection of phosphorylated H2AX histones) in the development of apoptotic events. WP 631 demonstrated significantly higher effectiveness as a pro-apoptotic drug than DOX. This was evident in the higher levels of markers of apoptosis, such as the externalization of phosphatidylserine and the elevated level of cytochrome c. An extension of incubation time led to an increase in intracellular calcium levels after treatment with DOX. Lower changes in the calcium content were associated with the influence of WP 631. DOX led to the activation of all tested caspases, 8, 9 and 3, whereas WP 631 only induced an increase in caspase 8 activity after 24h of treatment and consequently led to the cleavage of PARP. The lack of active caspase 3 had no outcome on the single and double-stranded DNA breaks. The obtained results show that WP 631 was considerably more genotoxic towards the investigated cell line than DOX. This effect was especially visible after longer times of incubation. The above detailed studies indicate that WP 631 generates early apoptosis and cell death independent of caspase-3, detected at relatively late time points. The observed differences in the mechanisms of the action of WP631 and DOX suggest that this bisanthracycline can be an effective alternative in ovarian cancer treatment.

Anti-proliferation Effects of Isorhamnetin on Lung Cancer Cells in Vitro and in Vivo

  • Li, Qiong;Ren, Fu-Qiang;Yang, Chun-Lei;Zhou, Li-Ming;Liu, Yan-You;Xiao, Jing;Zhu, Ling;Wang, Zhen-Grong
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.7
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    • pp.3035-3042
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    • 2015
  • Background: Isorhamnetin (Iso), a novel and essential monomer derived from total flavones of Hippophae rhamnoides that has long been used as a traditional Chinese medicine for angina pectoris and acute myocardial infarction, has also shown a spectrum of antitumor activity. However, little is known about the mechanisms of action Iso on cancer cells. Objectives: To investigate the effects of Iso on A549 lung cancer cells and underlying mechanisms. Materials and Methods: A549 cells were treated with $10{\sim}320{\mu}g/ml$ Iso. Their morphological and cellular characteristics were assessed by light and electronic microscopy. Growth inhibition was analyzed by MTT, clonogenic and growth curve assays. Apoptotic characteristics of cells were determined by flow cytometry (FCM), DNA fragmentation, single cell gel electrophoresis (comet) assay, immunocytochemistry and terminal deoxynucleotidyl transferase nick end labeling (TUNEL). Tumor models were setup by transplanting Lewis lung carcinoma cells into C57BL/6 mice, and the weights and sizes of tumors were measured. Results: Iso markedly inhibited the growth of A549 cells with induction of apoptotic changes. Iso at $20{\mu}g/ml$, could induce A549 cell apoptosis, up-regulate the expression of apoptosis genes Bax, Caspase-3 and P53, and down-regulate the expression of Bcl-2, cyclinD1 and PCNA protein. The tumors in tumor-bearing mice treated with Iso were significantly smaller than in the control group. The results of apoptosis-related genes, PCNA, cyclinD1 and other protein expression levels of transplanted Lewis cells were the same as those of A549 cells in vitro. Conclusions: Iso, a natural single compound isolated from total flavones, has antiproliferative activity against lung cancer in vitro and in vivo. Its mechanisms of action may involve apoptosis of cells induced by down-regulation of oncogenes and up-regulation of apoptotic genes.

Effects of Chungkukjang Added with Onion on Lipid and Antioxidant Metabolisms in Rats Fed High Fat-Cholesterol Diet (양파 첨가 청국장이 고콜레스테롤혈증 유발 흰쥐의 지질 및 항산화 대사에 미치는 영향)

  • Park, Jae-Hee;Kim, Jung-Mi;Park, Eun-Ju;Lee, Kyung-Hea
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.10
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    • pp.1244-1250
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    • 2008
  • This study was carried out investigate the effects of chungkukjang added with onion (OC) and chungkukjang (C) on the lipid and antioxidant metabolisms of hypercholesterolemic rats. Thirty-two male Sprague-Dawley rats were divided into four groups after 1-week adaptation period and were fed a normal diet, high fat-cholesterol diet (HC), HC-OC or HC-C for 8 weeks, respectively. The supplementation of HC-OC and HC-C groups significantly reduced hepatic total cholesterol and AST activity. HC-C group increased high density lipoprotein, while decreasing low density lipoprotein and AI compared with HC-OC group. Conjugated dienes of HC-C group was significantly lower than those of HC-OC group. $H_2O_2$ induced DNA damage reduced significantly in HC-OC and HC-C groups compared with high fat-cholesterol diet group. $H_2O_2$ induced DNA damage exhibited significant positive correlations with hepatic total cholesterol, AST and CD. These results suggested that supplementation of chungkukjang or chungkukjang added with onion might be helpful in preventing lipid oxidation and leukocytic DNA damage. However, the health beneficial effect has not improved by the addtion of onion in chungkukjang.

In Vitro and In Vivo Anti-Oxidative and Anti-Inflammatory Activities of Acer tegmentosum Maxim Extracts (RAW 264.7 대식세포와 염증유도 동물모델에서 산겨릅나무 추출물의 항산화 및 항염증 효과)

  • Lee, Cho-Eun;Jeong, Hyeon-Hee;Cho, Jin-Ah;Ly, Sun Yung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.1
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    • pp.1-9
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    • 2017
  • Acer tegmentosum Maxim (ATM) is known as traditional medicine for treatment of hepatic disorders such as hepatitis, related-inflammatory disease, and hepatic cancer. In this study, we evaluated the antioxidant and anti-inflammatory effects of ATM extracted with $80^{\circ}C$ water or 95% ethanol. Antioxidant activities of ATM extracts were measured based on DPPH and ABTS radical scavenging activities, total polyphenolic compound contents, and ferric reducing antioxidant power. The anti-inflammatory effects of ATM extract were assayed on release of nitric oxide, tumor necrosis factor $(TNF)-{\alpha}$, and interferon $(IFN)-{\gamma}$ from lipopolysaccharide (LPS)-induced macrophages. In these experiments, 95% ethanol extract of ATM showed stronger antioxidant and anti-inflammatory effects than water extract. Therefore, we determined the effects of ATM ethanol extract on an animal model of sepsis. Seven days oral gavage of ATM ethanol extract followed by LPS stimulation reduced the protein levels of $TNF-{\alpha}$ and $IFN-{\gamma}$ in serum as well as mRNA levels of $TNF-{\alpha}$ and interleukin-6 in intestinal epithelial cells. In addition, ATM ethanol extract reduced DNA damage in mouse lymphocytes. These results indicate that ATM extract has strong antioxidant and anti-inflammatory in vitro and in vivo effects and may be developed as a potential food material for prevention of inflammatory diseases.

Protective Effects of a Herb, Artemisia capillaris, Against Radiation-induced DNA Damage (방사선 유도 DNA 손상에 대한 인진쑥의 방어효과)

  • Jo, Sung-Kee;Oh, Heon;Cheon, Eui-Hyun;Jeong, U-Hee;Cho, Nam-Jeong
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.1
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    • pp.22-27
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    • 2004
  • In the present study, the protective effects of Artemisia capillaris (AC) on the DNA damage induced by $^{60}$ Co ${\gamma}$-rays were evaluated using alkaline single-cell gel electrophoresis (SCGE, comet assay) in the mouse peripheral lymphocytes and micronuclei (MN) formation test in the Chinese hamster ovary (CHO) cells. We also investigated the effect of AC on 8-hydroxy-2'-deoxyguanosine (8-OHdG) formation in the mouse liver and thymus exposed to ${\gamma}$-ray, The tail moment and the frequency of MN, which were markers of DNA damage in the SCGE and MN formation test, were decreased in the groups treated with AC extract before exposure to 200 cGy of ${\gamma}$-ray. We also observed its activities, lowering 8-OHdG level, an index of oxidative DNA damage, in the groups treated with AC extract before whole body ${\gamma}$-irradiation (800 cGy). It is plausible that scavenging of free radicals by AC may have played an important role in providing the protection against the radiation-induced damage to the DNA. These results indicated that AC protects the DNA damage induced by ${\gamma}$-rays and might be a useful radioprotector, especially since it is a relatively nontoxic product.

No Relationship between the Amount of DNA Damage and the Level of hMLH1 and RASSF1A Gene Expression in Bladder Cancer Cells Treated with Cisplatin and Gemcitabine

  • de Camargo, Elaine Aparecida;da Silva, Glenda Nicioli;Gobette, Camila Pereira;de Castro Marcondes, Joao Paulo;Salvadori, Daisy Maria Favero
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.10
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    • pp.5941-5948
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    • 2013
  • Tumor response to antineoplastic drugs is not always predictable. This is also true for bladder carcinoma, a highly recurrent neoplasia. Currently, the combination of cisplatin and gemcitabine is well accepted as a standard protocol for treating bladder carcinoma. However, in some cases, this treatment protocol causes harmful side effects. Therefore, we investigated the roles of the genes TP53, RASSF1A (a tumor suppressor gene) and hMLH1 (a gene involved in the mismatch repair pathway) in cell susceptibility to cisplatin/gemcitabine treatment. Two bladder transitional carcinoma cell (TCC) lines, RT4 (wild-type TP53) and 5637 (mutated TP53), were used in this study. First, we evaluated whether the genotoxic potential of cisplatin/gemcitabine was dependent on TP53 status. Then, we evaluated whether the two antineoplastic drugs modulated RASSF1A and hMLH1 expression in the two cell lines. Increased DNA damage was observed in both cell lines after treatment with cisplatin or gemcitabine and with the two drugs simultaneously, as depicted by the comet assay. A lack of RASSF1A expression and hypermethylation of its promoter were observed before and after treatment in both cell lines. On the other hand, hMLH1 downregulation, unrelated to methylation status, was observed in RT4 cells after treatment with cisplatin or with cisplatin and gemcitabine simultaneously (wild-type TP53); in 5637 cells, hMLH1 was upregulated only after treatment with gemcitabine. In conclusion, the three treatment protocols were genotoxic, independent of TP53 status. However, cisplatin was the most effective, causing the highest level of DNA damage in both wild-type and mutated TP53 cells. Gemcitabine was the least genotoxic agent in both cell lines. Furthermore, no relationship was observed between the amount of DNA damage and the level of hMLH1 and RASSF1A expression. Therefore, other alternative pathways might be involved in cisplatin and gemcitabine genotoxicity in these two bladder cancer cell lines.

Lymphocyte DNA Damage and Anti-Oxidative Parameters are Affected by the Glutathione S-Transferase (GST) M1 and T1 Polymorphism and Smoking Status in Korean Young Adults (흡연 여부에 따른 Glutathione S-transferase (GST) M1 및 T1 유전자 다형성이 우리나라 젊은 성인의 임파구 DNA 손상과 항산화 영양상태 지표들 간의 관련성에 미치는 영향)

  • Han, Jeong-Hwa;Lee, Hye-Jin;Kang, Myung-Hee
    • Journal of Nutrition and Health
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    • v.44 no.5
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    • pp.366-377
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    • 2011
  • Glutathione S-transferase (GST) is a multigene family of phase II detoxifying enzymes that metabolize a wide range of exogenous and endogenous electrophilic compounds. GSTM1 and GSTT1 gene polymorphisms may account for inter-individual variability in coping with oxidative stress. We investigated the relationships between the level of lymphocyte DNA and antioxidative parameters and the effect on GST genotypes. GSTM1 and GSTT1 were characterized in 301 young healthy Korean adults and compared with oxidative stress parameters such as the level of lymphocyte DNA, plasma antioxidant vitamins, and erythrocyte antioxidant enzymes in smokers and non smokers. GST genotype, degree of DNA damage in lymphocytes, erythrocyte activities of superoxide dismutase, catalase, and glutathione peroxidase (GSH-Px), and plasma concentrations of total radical-trapping antioxidant potential (TRAP), vitamin C, ${\alpha}$- and ${\gamma}$-tocopherol, ${\alpha}$- and ${\beta}$-carotene, and cryptoxanthin were analyzed. Lymphocyte DNA damage assessed by the comet assay was higher in smokers than that in non-smokers, but the levels of plasma vitamin C, ${\beta}$-carotene, TRAP, erythrocyte catalase, and GSH-Px were lower than those of non-smokers (p < 0.05). Lymphocyte DNA damage was higher in subjects with the GSTM1- or GSTT1-present genotype than those with the GSTM1-present or GSTT1- genotype. No difference in erythrocyte antioxidant enzyme activities, plasma TRAP, or vitamin levels was observed in subjects with the GSTM1 or GSTT1 genotypes, except ${\beta}$-carotene. Significant negative correlations were observed between lymphocyte DNA damage and plasma levels of TRAP and erythrocyte activities of catalase and GSH-Px after adjusting for smoking pack-years. Negative correlations were observed between plasma vitamin C and lymphocyte DNA damage only in individuals with the GSTM1-present or GSTT1- genotype. The interesting finding was the significant positive correlations between lymphocyte DNA damage and plasma levels of ${\alpha}$-carotene, ${\beta}$-carotene, and cryptoxanthin. In conclusion, the GSTM1- and GSTT1-present genotypes as well as smoking aggravated antioxidant status through lymphocyte DNA damage. This finding confirms that GST polymorphisms could be important determinants of antioxidant status in young smoking and non-smoking adults. Consequently, the protective effect of supplemental antioxidants on DNA damage in individuals carrying the GSTM1- or GSTT1-present genotypes might show significantly higher values than expected.